This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The high-flux beam lines at third generation synchrotrons produce very high intensity x-radiation. Unfortunately, due to decay of the protein crystals in the high intensity beam, the synchrotrons users insert attenuators to reduce the beam intensity. Therefore, beam lines are not utilizing their full potential for protein diffraction experiments. There have been several attempts to study the mechanisms of protein crystal decay. The common belief is that the radiation decay is partly due to the effect of the radicals produced by the interaction of x-ray photons with the protein or solvent atoms in the crystal. Researchers have used various procedures like lowering the data collection temperature, incorporating radical scavengers, etc. to reduce the effect of these radicals. The current project tries to address the radiation decay of protein crystals by employing few selected gases as radical scavengers.